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<br /> 1.02. The Property is being remediated pursuant to a Oversight and
<br /> Consultation Agreement pursuant to Chapter 6.8 of Division 20 of the Health and Safety
<br /> Code, under the oversight of the Department. A Revised Preliminary Endangerment
<br /> Assessment Report, approved by the Department on March 13, 2000, requires that a
<br /> deed restriction be recorded as part of the site remediation, because lead, benzo (a)
<br /> pyrene, benzene, toluene, ethylbenzene, xylenes, methyl tert-butyl ether (MTBE), which. -
<br /> are hazardous substances, as defined in H&SC section 25316, and a hazardous
<br /> material as defined in H&SC section 25260, were detected in groundwater, soil, and
<br /> sediment samples, below the surface of the Property. Pursuant to the California
<br /> Environmental Quality Act, Public Resources Code section 21000 et seq_., the
<br /> Department has reviewed a Draft Supplemental Environmental Impact
<br /> Report/Environmental Assessment (Draft EIR/EA) dated January 12, 2000:: The
<br /> Department commented on the Draft EIR/EA in a letter dated February 23, 2000. Both
<br /> the Draft EIR/EA and the Department's comment letter identified the need fora deed
<br /> restriction for the Weber Block Project.
<br /> 1.03. As detailed in the Revised Preliminary Endangerment Assessment
<br /> -approved by the Department on March 13, 2000, all or a portion of the subsurface soil,
<br /> and sediment within the Stockton Channel of the Property contain hazardous
<br /> substances, as defined in H&SC section 25316, which include the following
<br /> contaminants of concern at the following maximum concentration: benzo (a) pyrene
<br /> (1.2 milligram/kilogram(mg/kg)),lead (206 mg/kg), and arsenic (22.1 mg/kg). .
<br /> Groundwater near the former Shell site on the Property ranged from 16 to 19 feet below ,
<br /> ground surface during the monitoring events conducted in July 1998, October 1998,
<br /> January 1999, and April 1999. Maximum contaminant concentrations in groundwater
<br /> monitoring of eleven wells include: benzene (2.6 milligrams/liter (mg/1)), toluene (8.3
<br /> mg/i), ethylbenzene (2.2 mg/1), xylenes (9.5 mg/1), methyl tertiary-butyl ether (MTBE)
<br /> (1.75 mg/1), and total petroleum hydrocarbons (47 mg/1). Maximum contaminant
<br /> concentration in an unfiltered groundwater sample collected from the south side of the
<br /> Stockton Channel contained lead at 75.3 ug/I. In a Report.dated October 6,'.2000, by ,
<br /> Baseline Environmental Consulting, the groundwater in the area from the south side of
<br /> the Stockton Channel was re-sampled. This sample was filtered prior to analysis. The
<br /> analysis of this groundwater sample for total lead was reported at a concentration of
<br /> less than 3.0 ug/l, the'laboratoryreporting limit. ,
<br /> Based on the Final Risk Assessment the calculated excess lifetime cancer risk from soil
<br /> ingestion and dermal contact for the Site was 2.3 x 10', which exceeds the 1 x 10-6
<br /> cancer risk level. The largest contributor to the risk from this exposure pathway was
<br /> from benzo(a)pyrene. The excess lifetime cancer risk from groundwater ingestion and
<br /> showering/bathing with volatile organic compounds and non-volatile organic r
<br /> compounds; as calculated using on-site groundwater data, was 1.1 x 10-5. The largest
<br /> contributor to the risk from this exposure pathway was benzene. The cumulative
<br /> excess cancer risk from soil ingestion and dermal contact, groundwater ingestion and
<br /> showering/bathing with shallow groundwater underlying the Site, ambient air, and
<br /> indoor air was calculated to be 3.3 x 10-5. i
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